coolant temp sensor

[dagenham]

Is there anything in the coolant system electrics besides the coolant temp sensor , the module under the dash, and the electric fan???
My car got hot sitting in traffic tonight and when I parked it and shut it off, thats when the steam rolled. I opened the hood and realized the fan was not running. I replaced the module under the dash already due to it making a buzzing noise about two years ago. The fan runs if I hot wire it. So I'm thinking it is the coolant temp sensor.
Anyone have any other suggestions, or does the sensor seem to be the next logical step??

[scenario]

If you turn the defroster or A/C on the fan will kick on. I do that sometimes if in traffic and the gauge starts creeping into the scary zone.

I replaced the coolant temp sensor last year, thinking it was not working properly but even with the new one it gets hot in traffic sometimes. The fan will kick on sometimes when it is supposed to but I think the dash gauge is not all that accurate with actual temperature. I am sure others with more knowledge on this will chime in here.

Maybe there is something else that I failed to realize when I was troubleshooting my car. Like I said before mine does not always act up, just sometimes and I am only going by the factory "NORMAL" gauge.

[FoxBuddy]

I honestly don't think I've seen my fan come on but I don't think I have hit the "danger" zone or seen steam. I'm interested on your fault test methods.

[FinnSVO]

I have had same issue. Replaced module (it was original and shot) and temp switch and installed on/off switch to dashboard (grounding wire #1 from module harness). Fan works as supposed with AC as well as using switch or grounding temp switch wire but not when temp goes to "danger" zone. I don't trust to stock gauge anymore and have installed real one as well as measured real temperature with infrared gauge from upper rad hose and temp switch area from engine. No matter how hot it runs (I have no guts to let it run much over 115 C / 240 F) but fan does not kick on. Maybe I just have bad luck and new temp switch is bad. Have to see on next winter, drive this summer using fan manually.

At least in my case factory gauge was clearly out of zone. Needle was on red zone but real temp was around 100C / 215F. Cheap infrared gauge is good tool with temp problems. I also have voltage regulator on back of gauge cluster on my "to do" list. Maybe it helps with gauge troubles, since also my oil press gauge is showing pressure "by it's own will"

[dagenham]

I turned on the a/c switch on Saturday morning after letting it idle and get hot, but it didnt kick the fan on. The clutch on the a/c compressor didnt kick either, but I expected that because there isnt any freon in the system(I need to fix that). I hot wired the fan direct to the battery for a few minutes and it cooled down nicely.
I ordered a sensor today so Ill find out later this week when I get to put it in.

[brsvo]

I gave up years ago and got an aftermarket fan controller that goes in the upper radiator hose. Has a knob to set it where you want. Wired it to the battery with a new relay to take the load off the switch.

[JTurbo]

I have a bypass / manual fan on-off switch under the dash on both of mine. Any time I'm in traffic, I just throw the switch to "ON".

Gave up on the factory controller.....

[svono50]

If your A/C isn't charged, it won't trigger the A/C's pressure switch to then trigger the compressor clutch and fan to kick on, so no surprises there. The factory cooling fan temp sensor is set to 226 deg F, which will likely show up at the very top of the normal range on the temp gauge. I too don't like to see things cook to that level before the fan kicks on, so I added a manual switch to ground out the factory fan relay by tapping into the yellow w/red stripe wire, which is what goes to the temp sensor. Even sitting still in traffic with the fan on, the temp gauge never goes over "O" on NORMAL on my car.

[dagenham]

Well I tried the temp sensor and it didnt fix the problem.
I will probably wire up a manual switch.

[svono50]

Did you pop the cap or did you just get too nervous before shutting down?? Mine won't turn on till the temp gauge hits the "H", so there is a bit of calibration issue with the dash gauge where it shows high.

[dagenham]

It actually started blowing past the rad cap, so I hotwired the fan direct to the battery and left the car run to actually cool it down.

[svono50]

Yep, definitely cooked it with that happening. Good call on hot wiring the fan and letting it cool that way. Have you checked the fan relay under the dash to make sure it isn't crispy on the power connections? They generally get a bit burned out over time and cause it to not be able to transfer the power to the fan.

[dagenham]

Yep, definitely cooked it with that happening. Good call on hot wiring the fan and letting it cool that way. Have you checked the fan relay under the dash to make sure it isn't crispy on the power connections? They generally get a bit burned out over time and cause it to not be able to transfer the power to the fan.

You know I never even thought about a relay. Now to sound dumb, where is it???

[svono50]

Black box, approx 2x3" located under the dash just to the left of the steering column. Below is a pic I found with a quick Google search, it even shows a good burnt power wire! Here is a link that has some good info from over on the foureyedpride forum:

http://vb.foureyedpride.com/showthread.php?128362-Cooling-fan-control-Relay-problem


7404
(http://vb.foureyedpride.com/showthread.php?128362-Cooling-fan-control-Relay-problem)

[dagenham]

OH, I already replaced that a few years ago. But I will double check the wiring to look for something burnt.

[Meotchh]

You can also unplug the pressure switch for the a/c & just jumper the plug. That should kick the fan on if the relay module is working.